My daughter and son-in-law have a house built in 1949. It has lath and plaster walls. They want to install a shower in their tub and tile the stall. One of the three walls is an exterior wall. Do we strip the:confused: walls back to studs and then use backerboard and seal it or should we install green board behind the cement board? How do you demo just the stall without damaging the rest of the plaster? Or should we just demo the entire room and start fresh?

What did you end up doing? I have a 50 yo house with plaster walls and the 2nd bathroom is destroyed by an old leak and termites. At least half the room will have to be gutted, but maybe there is something I can learn from! :)

I am very disappointed that no one has offered any advice. The project begins Monday, the 27th. I think that we will just demo the portion around the shower and use cement board and then seal it. I'm not sure about the ceiling, don't want to demo if we don't have to. Maybe just cover over the plaster with sheet rock? I will record our progress. The bathroom is between the babies room and the master bedroom so keeping the mess down is important too.

The first thing to consider is your waterproofing method of choice. Neither grout nor tile are waterproof. Greenboard is no longer acceptable in wet area locations according tht eht new TCNA guidelines.

Your choice of waterproofing is going to be one of the following which will determine what advice is best to give on how you proceed;

My daughter and son-in-law have a house built in 1949. It has lath and plaster walls. They want to install a shower in their tub and tile the stall. One of the three walls is an exterior wall. Do we strip the:confused: walls back to studs and then use backerboard and seal it or should we install green board behind the cement board? How do you demo just the stall without damaging the rest of the plaster? Or should we just demo the entire room and start fresh?

It would be the best thing to strip the walls back to the studs for a couple of reasons. Chances are there is some water damage and possibly mould after all these years. This allows the opportunity to correct those issues.
Also, there probably isn't much insulation within the exterior wall which can be easily addressed when the walls are stripped.

Considering it's lathe and plaster there will be some consequential cracking when you cut away the sections being removed that will need repairing.
One thing I do is screw a 2x4 or 1x4 vertically at the cutoff point. Use as many screws as you can and fasten the 2 by or 1 by into as many pieces of lathe as you can. Then patiently by using a reciprocating saw cut along that 2 by or 1 by, that piece you fastened will help minimizing the plaster from breaking away from the side you want to keep.

As for what to use, if your are tiling then use cement backer board with a waterproofing membrane like the Kerdi by Schulter or this neat product also by Schluter . It's a backer board with the waterproofing memebrane applied.
Check this http://www.kerdi-board.com/

Unfortunately the demo will be messy work, no getting around it. If you tent off as much area as you can will minimize the dust travelling to other areas of the home.

Thank you very much. I really like the idea of screwing the board to the lath to minimize lateral damage. I am not familiar with the sealer products listed. Will the sealer be in the same section of the store as the cement board and tile? I am concerned about the ceiling. Will I be able to leave it as is or should I take it out too?

Where are you located? Kerdi is also sold over the internet, but Schluter (the manufacturer) has an odd distribution system and doesn't allow all sellers to sell to all states. When you place an order, make sure they ship to your state.

We are in Eastern Washington State. We have Home Depot and Lowes nearby. We found some roll- on sealer at HD and are going to try that. We were able to keep the ceiling intact and make a splice between the cement board and the lath and plaster. It is taking much longer than we planned on. Our expectations for the time line were based on how quickly the all of the TV shows that we've watched were able to finish. I didn't expect to be finished in 1/2 an hour but we were hoping to be in and out in 3-3 1/2 days. So far it's taken us 4 days and we don't have the tile or the exhaust fan up yet. Whenever I do one of these projects my respect is renewed for the tradesmen who do this all of the time. My hat is off to all of you hard working people, especially the plumbers. (Sweating copper looks so easy on TV). Monday should get us mostly ready for tile.

Well, after 4 1/2 months, 2 or 3 bouts of gall bladder attacks and various other maladies my son-in-law took his first shower. If at all possible I will post pictures soon. I struggled with sweating copper to brass, the sealer was a brush on that was very odiferous, the walls weren't square which added another layer of complexity, trying to figure out how to tile around the window, the one wall that we sheet rocked took forever to finish. Working around our joint schedules, especially my toddler granddaughters nap times and such. It was like wadding through waste deep mud. When I told my son-in-law that I was planning on using a fiberglass kit for my own bathroom instead of tile he said that he would never tile again. Blending the width of the tile wall with the existing plaster was a dusty disaster. Fortunately I had a heavy duty full face respirator. After completely finishing the shower stall we realized that we hadn't fixed the drain but a little snake action and it started to work. The moral is that it can be done but it will take a lot of time. Ask your self if you enjoy challenges and if can you wait for it. I heard a good saying recently. With an old house the only thing that works is the homeowner.